Roshel buys a coat, a windbreaker, a dress and a blazer. The average cost of these items is $25. The total cost of the dress and the blazer is ²₃ of the total cost of the coat and the windbreaker. If the coat costs $14.50 and the blazer costs $6.80, find the difference in cost between the windbreaker and the dress.
Total cost of the 4 items
= 4 x 25
= $100

Total cost of the dress and the blazer = 2 u
Total cost of the coat and the windbreaker = 3 u

Total cost of the 4 items
= 2 u + 3 u
= 5 u

5 u = 100

1 u = 100 ÷ 5 = 20

Total cost of the dress and the blazer
= 2 u
= 2 x 20
= $40

Cost of the dress
= 40 - 6.80
= $33.20

Total cost of the coat and the windbreaker
= 3 u
= 3 x 20
= $60

Cost of the windbreaker
= 60 - 14.50
= $45.50

Difference in cost between the windbreaker and the dress
= 45.50 - 33.20
= $12.30

Answer(s): $12.30